What is the difference between 401 and 403?

401 Unauthorized means authentication is required or has failed, while 403 Forbidden means the server understood the request but refuses to authorize it regardless of credentials.

When should I use 301 vs 302?

Use 301 Moved Permanently when a resource has a new permanent URL (search engines update their links), and 302 Found for a temporary redirect where the original URL should still be used.

HTTP Status Code Reference

A fast, searchable reference of every HTTP status code with its name, meaning, and when to use it — from 1xx informational through 5xx server errors. Filter by class or search by code or text.

How to use HTTP Status Code Reference

Search by code (e.g. 404) or by name and description.
Filter by class: 1xx, 2xx, 3xx, 4xx, or 5xx.
Click a code to copy it.

Frequently asked questions

What is the difference between 401 and 403?: 401 Unauthorized means authentication is required or has failed, while 403 Forbidden means the server understood the request but refuses to authorize it regardless of credentials.
When should I use 301 vs 302?: Use 301 Moved Permanently when a resource has a new permanent URL (search engines update their links), and 302 Found for a temporary redirect where the original URL should still be used.

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